"Even more important than your putting or your ball striking is taking on the right shots at the right time," says Harrington of his prudently bold Masters plan.

Padraigh Harrington's slow, steady rise to superstardom has been built on precise, calculating golf ("I tend to be more conservative, always with one eye on a good place to miss," Harrington says), but as he arrives at this Masters on the precipice of so much history, he knows his best chance at a green jacket is to abandon who he is as a golfer. "I need to be a bit more gung ho," Harrington says. "The most important thing at Augusta, the Number 1 priority, is making the right decisions. Even more important than your putting or your ball striking is taking on the right shots at the right time. I need to be committed to taking risks on the course."

In Harrington's first seven Masters he finished better than 13th only once (fifth in 2002). In the last two, he tied for seventh and then last year shared fifth, part of an ascension that has seen him win two British Opens and a PGA Championship in the last 21 months. At this Masters he will try to join Bobby Jones, Ben Hogan and Tiger Woods as the only men to triumph at three consecutive major championships, and Harrington's tolerance for aggression will be tested on the very first hole. He has bogeyed number 1 in five of his last 12 rounds at Augusta National. "I find the green to be the toughest on the course, with some very severe pin positions," he says. "I've tried to play to certain spots, but there is no good place to miss. You either hit it close or you may be off the green. So you might as well fire at the flag, you know?"

This do-or-die philosophy is even more pronounced on the hole that has defined so many Masters, the sharply doglegged par-5 13th, with the left side of its fairway and green protected by Rae's Creek. From 2002 to '06 Harrington played the reachable hole cautiously and was a cumulative even par in 18 rounds. "I always laid up off the tee with three-wood or four-wood," he says. "It made the drive less risky. That left me with a five-wood in, so I was usually quite happy [if I] put it in the middle of the green."

Over the last two years Harrington has unsheathed his driver, flying the trees on the inside corner of the dogleg and hugging the left side, flirting dangerously with the creek. He has often been rewarded for the gambit: With only a four- or a five-iron to the green, he made two birdies and an eagle in 2007 and last year had two birdies (but also a bogey). "The difference is that when I get it wrong, it's going to go badly, and I'll take 7 or close to it," Harrington says. "I'm working on the principle that some year it's going to go horribly wrong, but if I want to win the tournament, I have to take the chance."

Harrington, 37, is the rare golfer who can find validation in failure. The 2006 U.S. Open is remembered for the 72nd-hole self-immolation of Phil Mickelson and, to a lesser degree, Colin Montgomerie, but Harrington had his own blowup at Winged Foot, bogeying the final three holes to finish two back of Geoff Ogilvy. Yet Harrington has often said that the peace he felt playing that final round left him convinced he was ready to win a major, and 15 months later he did, at Carnoustie. Similarly, his commitment to attacking Augusta National was fortified in 2007 with a shot that he says ultimately left him "gutted."

Harrington had begun the final round two strokes off the lead but struggled in the brutally cold and windy conditions, playing the first 11 holes in three over. A birdie at 12 and an eagle at 13 got him back in the game. Three off the lead playing the par-5 15th hole, he smoked a drive and had 232 yards to the flag, a comfortable distance for his hybrid. "It was pure," he says of the strike. "It was dead at the flag. In the air I was thinking I was going to make eagle and be one back. Then a gust of wind knocked the ball down. It landed on the green but pitched back into the water. I couldn't believe it. I never thought it was short. One more yard and it winds up 20 feet from the flag. Three more yards and it's stone dead.

"People afterward second-guessed the play, saying, Oh, God, you lost the Masters there. But I wasn't going to win by laying up. Of course I was gutted with the result, but not the decision. I would have been more gutted never to have had the chance to win. I will sacrifice everything simply for the chance to win."

FOR HARRINGTON, who makes his home in Dublin, the road to Augusta leads through the scruffy hamlet of Largs on Scotland's rugged Ayrshire coast, where he spends every wet, miserable winter fine-tuning his game under the watchful eye of Bob Torrance, the 77-year-old oracle whose hundreds of pupils include his son Sam, the victorious 2002 Ryder Cup captain. Harrington first sought out the elder Torrance following the 1998 U.S. Open, during which he felt overmatched trying to control his approaches into the brick-hard greens at the Olympic Club. Harrington has grown so close to his teacher that he has his own brass bed in a spare room in Torrance's cottage, and his favorite meal, a Dover sole that is straight off the trawler, is cooked by Bob's bride, June. Torrance is old school in the extreme: no video cameras, no mirrors, and even the champion golfer of the world shags his own balls at the low-tech driving range where Torrance plies his trade.

After the greatest season of his career, Harrington still spent time last winter visiting Torrance. The two focused on improving Harrington's iron play, which was already quite proficient. "You have got to get the strike right," Torrance growls in a brogue that has been flavored by a lifetime of the cigarettes and coffee that help fortify him against the elements. "He is trying to come at the ball steeper to get more penetration in his flight. Instead of dropping straight down, the ball will come in high, but it will still be going forward when it is landing. There will be more backspin on the ball. A ball that drops straight down from the sky is not going to come back. But a ball that comes in lower with spin is going to go forward and then screw back. We are getting steep on the ball so that he can compress the ball more, the way Jimmy Bruen used to do." It's an allusion only Torrance could make  Bruen was a great Irish amateur who starred at the 1938 Walker Cup.

Harrington's swing changes are part of his relentless quest for improvement, but being ready for this Masters was surely an influence. "Controlling the distance on your approaches is absolutely vital at Augusta," he says. Harrington spent much of the 2009 West Coast swing toiling to groove the changes. His middling results  missed cuts at Riviera and Pebble Beach, a first-round loss at the Match Play  led to a certain amount of consternation among an Irish public that is heavily invested in his progress, but Harrington was using those events as little more than spring training.

Relaxing in the clubhouse at Doral three weeks ago, he said, "I've been caught up in the swing and technique. I've been more than happy to close down the range many nights. Now it's time to trust it and simply go out and play." Shortly after uttering those words, he shot his best round of the year, a carefree 66 that put him one off the lead at the CA Championship. Harrington followed with three 71s to finish 20th and was buoyant with his progress. Last week at Bay Hill he turned in three scores of par or better and finished 11th.

Of course, this is all preamble, and the unique rigors of the Masters make it foolish to read too much into the run-up. Harrington has already proved he's among the few players who can will himself into peaking for the game's biggest events. Speaking after Doral, Torrance said of his pupil, "He is feeling very, very confident. He might not say it publicly, but Padraig knows that there isn't a player out there he can't beat. Not one. He's frightened of nobody. He would be more than happy to go out and play the last 18 holes at the Masters tied for the lead with Tiger. That would suit him down to the ground."

Woods was on the disabled list for last year's British Open and PGA Championship, but any talk of a metaphorical asterisk was quieted by Harrington's brilliance in shooting 32s on the final nine holes at Royal Birkdale and Oakland Hills. Halfway to matching the Tiger Slam, Harrington says, "I don't have to win the Masters this year to prove anything. I can easily get drawn into the hype about trying to win three [majors] in a row, but that is not what is driving me. I want to win the tournament because it's always been a dream, simple as that. Offer me a missed cut this year and a win next year, and I'll take it very nicely."

EVERYTHING ABOUT this Masters week is designed to allow Harrington to have fun and stay mellow. For the first time his five-year-old son, Patty, will caddie during the par-3 contest, which Harrington won in 2003 and '04. Many competitors are shooting for second place on Wednesday because, famously, no one has won the par-3 and the Masters in the same year. "I'm hoping to win both just to prove that superstition is a bunch of rubbish," says Harrington.

In the evenings he will retire to a house rented by a longtime golf buddy  private by nature, Harrington declines to give a name  who plays host to a sprawling cast of Harrington's friends and family members at every Masters. Dinners are catered, and afterward Harrington and his pal renew a gin rummy grudge match that is a decade in the making. "It's serious," he says. "Real serious. I will try as hard with that as I do playing golf during the day. It's a great distraction for my mind."

It is what's between his ears that separates Harrington as a player from his peers. He is not an overwhelming physical talent, and the game has never come easy to him. Before he turned pro in 1995, at the advanced age of 24, he earned an accounting degree because he was so unsure of his playing prospects that he wanted to have something to fall back on. Over his first six seasons on the European tour Harrington had 15 runner-up finishes against four victories, giving him a rep as a player who couldn't close the deal. Even now, after so much success, he says, "I play the game based on fear. I like the situation where I know the other guy has fear in him too. No doubt that's the case during the last nine holes of the Masters. Other tournaments, other times, you're not too sure what the other guy is feeling. Back nine on Sunday at Augusta, you know exactly what he's feeling. Because I've always played with that fear, there's a good chance I'll be able to manage better than him."

Torrance eschews the touchy-feely aspects of golf, but he has helped Harrington learn to embrace the big moment. Says Torrance, "All I tell him is this: These are the happiest days of your life. Go out and enjoy them. And he has."

For Harrington the exquisite joy and pain of the Masters will only be experienced if he steps to the 10th tee of the final round in the thick of the action. "The Masters is unique because the first 63 holes are simply jockeying, and then it's a nine-hole sprint to the finish," Harrington says. "The back nine at Augusta is the most intimidating set of holes in the world. Coming down the back nine with a chance to win  you know you're alive then." And if his calculations have been correct, Harrington will be in position to risk everything for a shot at the green jacket.